very large dump truck / sand / buried EV
The dirt cover idea doesn’t really apply to a battery fire. It’s not using oxygen Think like an electric arc welder. The heat and fire is from the electric short and it just keeps arcing. There does need to be an emergency way to draw off the stored voltage like, to a really big light bulb. Even the giant water bath isn’t really putting out the fire-—just keeping it confined until the battery “runs down.”
I’ve seen people put a dry cell battery in their pocket with maybe loose change or keys. The battery shorts out and heats up the pocket. The fix is to either pull out the battery or shuck the pants-—quickly. Same problem only way bigger with the car.